What are the marine fenders on the wharves for?
We equip wharves with fenders that act as a cushion between the wharf and the vessel. They absorb the shock of the vessel when it approaches its berth and goes from a low speed to a full stop.
These marine fenders are there to protect the berth on Alexandra
pier where the Maasdam cruise ship is about to dock.
Even if a vessel’s speed has been reduced to a bare minimum, when it approaches the wharf to dock the strength of its inertia, the waves, the current and the wind propel it forward. Without buffer fenders, the sides of the ship would strike the concrete or metal of the wharf, causing damage to both the wharf and the vessel.
Historically, most fenders were made of rubber and most often, huge tires were used. “But the use of these recycled tires is disappearing, “ said Jean-François Belzile, the Port of Montreal’s Harbour Master and Director, Marine Operations. “It’s hard to measure their effectiveness because they are not all used the same way. Some crack easily. Next, their rubber is very hard and it can buffer the smaller ships, plus their shock absorption capacity is hard to measure.”
The methods are constantly being refined and the new marine fenders offer a whole other aspect. Now several types of models exist. The Port of Montreal is currently carrying out a project to modernize its wharf fenders, at a cost of $10 million over five years with the financial assistance of the Quebec government under its Maritime Strategy. Engineers from the Port of Montreal working with the Department of Marine Operations are making plans to prepare the wharves to receive the new fenders.
This fender is strong enough to handle the shack of large
merchant ships.The shield absorbs the pressure exerted by
the ship leaning against il. It protects both the dock and the
ship's hull at the same time.
Jean-François Belzile, Port
of Montreal's Harbour Master
and Director, Marine Operations
On some wharves, for example at the oil docks, we have already started replacing the tires with mechanical fenders. They have a higher shock absorption capacity than the tires so they are more effective when it comes to moorings high tonnage vessels.
At the Cruise Terminal we opted for floating fenders instead, which are 3.5 metres in diameter. Fenders have to be wide enough to provide three meters of space between the ship and the berth to allow enough room for the baggage cage to move. In addition, this type of fender can be easily moved to adapt their spacing configuration to the size of the vessels, which varies considerably.
There are cylindrical, conical and vertical fenders that all meet different needs, for example the size and therefore the weight of vessels, the curvature of the ship’s hull, the resistance of ice in winter, etc.
“In short, when it comes to marine fenders, there is no single solution for all vessels. There are lots of variables to consider,” said Jean-François Belzile.